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排序方式: 共有245条查询结果,搜索用时 31 毫秒
31.
Ekaterina E. Stoikova Michail I. Sorvin Dmitry N. Shurpik Herman C. Budnikov Ivan I. Stoikov Gennady A. Evtugyn 《Electroanalysis》2015,27(2):440-449
A novel potentiometric sensor based on screen‐printed carbon electrode covered with electropolymerized polyaniline (PANI) and unsubstituted pillar[5]arene as ionophore has been developed and tested in potentiometric measurements of pH and metal ions. The introduction of pillar[5]arene improved the reversibility of the pH response in the range from 2.0 to 9.0 with the slope of 45 mV/pH. Among metal cations, the response to Fe3+ and Ag+ ions was referred to PANI redox conversion whereas the signal toward Cu2+ in the range from 1.0×10?6 to 1.0×10?2 M (limit of detection (LOD) 3.0×10?7 M) to specific interaction with the macrocycle. 相似文献
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Alexander V. Stepakov Michail A. KinzhalovVitaly M. Boitsov Liubov V. StepakovaGalina L. Starova Sergey Yu. VyazminElena V. Grinenko 《Tetrahedron letters》2011,52(24):3146-3149
Reaction of N-aryl substituted maleimides with aliphatic ketazines leads to the formation of 4,5-dihydropyridazin-3(2H)-ones in moderate yields. The reaction proceeds through 1,4-addition of an azine to the maleimide double bond, as confirmed by separation of the corresponding adducts in some cases, which are then converted into 4,5-dihydropyridazin-3(2H)-ones. In addition, the solid-state synthesis of 4,5-dihydropyridazin-3(2H)-ones is demonstrated for the first time. 相似文献
34.
Andrey Yu. Manakov Andrey G. Ogienko Vladislav Yu. Komarov Aleksei I. Ancharov Michail A. Sheromov 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(3-4):317-320
X-ray diffraction study of quenched sample of acetone clathrate hydrate synthesized at 0.8 GPa was carried out. It was shown
that the host frameworks of the hydrate comprise uniform cavities which are similar to that of recently characterized structure
of high-pressure tetrahydrofurane hydrate. The unique peculiarity of investigated hydrate is decrease in the crystallographic
symmetry of the hydrate arising from ordering in guest subsystem. 相似文献
35.
Tatiana B. Mikenas Vladimir A. Zakharov Lyudmila G. Echevskaya Michail A. Matsko 《Journal of polymer science. Part A, Polymer chemistry》2005,43(10):2128-2133
Data on ethylene polymerization over supported LFeCl2/MgCl2 catalysts {L = 2,6‐bis[1‐(2,6‐dimethylphenylimino)ethyl]pyridyl} containing AlR3 (R = Me, Et, i‐Bu, or n‐Oct) as an activator are presented. These catalysts are highly active (100–300 kg of polyethylene/g of Fe h bar of C2H4) and stable in ethylene polymerization at 70–80 °C. Data on the effects of the iron content, AlR3 type, Al(i‐Bu)3 concentration, and hydrogen presence on the catalyst activity are presented. The molecular structure of polyethylene produced with these catalysts (including the molecular masses, molecular mass distribution, branching, and number of C?C bonds) has been studied; data on the effects of AlR3 and hydrogen on the molecular structure are presented. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2128–2133, 2005 相似文献
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Athanasekos L Vasileiadis M Tsigara A Kaminska E Piotrowska A Alexandropoulos D Sigalas MM Vainos NA 《Optics letters》2010,35(23):4003-4005
We designed and fabricated multilayer metal/metal-oxide surface relief diffractive grating structures by growing alternating Pt and SnO(x) layers. Optical interrogation at 633 nm reveals the temperature dependence of their reflection and transmission diffractive effects. This function is explored here in the context of a remote, spatially localized, photonic temperature sensing operation, achieving sensitivity of 10% per °C for the zeroth-order in the transmission mode. The experimental demonstration is found to be in good agreement with the results of rigorous coupled wave analysis of the composite metal/metal-oxide element. 相似文献
40.
Andrey N. Komogortsev Boris V. Lichitsky Alexander D. Tretyakov Artem N. Fakhrutdinov Arkady A. Dudinov Michail M. Krayushkin 《Journal of heterocyclic chemistry》2019,56(11):3081-3087
A convenient approach to the synthesis of the previously unknown 7H‐furo[3,2‐b]pyran‐7‐ones based on the intramolecular cyclization of carbonyl derivatives of 5‐hydroxy‐2‐methyl‐4H‐pyran‐4‐one has been elaborated. Key intermediates in the synthesis of the target 7H‐furo[3,2‐b]pyran‐7‐ones are 3‐hydroxy‐6‐methyl‐2‐(2‐oxo‐2‐arylethyl)‐4H‐pyran‐4‐ones. They are formed as a result of multicomponent condensation of 5‐hydroxy‐2‐methyl‐4H‐pyran‐4‐one with arylglyoxals and 4‐methoxyaniline. 相似文献